The airline industry has long used fasteners to mount passenger cabin trim panels to the airplane's fuselage structure. The fasteners that are used in this environment usually include a fastener element, such as a machine screw, and a fastener mount that is attached to a support member. Such fasteners are required to securely hold the trim panels in place, while also acoustically and thermally isolating the trim panel from the fuselage. Without proper acoustic isolation, a great deal of noise is transmitted into the passenger cabin. Without proper thermal isolation, a significant amount of heat is lost at the fastening point.
In the past, many prior aircraft trim panel fastener mounts have been constructed of aluminum or steel elements joined by a large, resilient, thick washer-shaped pad. The large, resilient, thick washer-shaped pad provided the desired acoustic and thermal isolation while the aluminum or steel elements provided the desired structural attachment strength. In this regard, the specifications for trim panel fastener mounts require that such mounts meet certain load requirements. While the load requirements vary depending upon the location of a fastener mount during use, the minimum requirements are that a fastener mount designed to receive a 0.1900 inch diameter, 32 UNF threads per inches screw inserted to a depth of 0.240 inches withstand the application of a load of 40 pounds in tension and shear to the screw without failure, i.e., separation between the screw and the fastener mount. Other fastener mounts are required to meet more than five times these tension and shear loads, i.e., tension and shear loads of up to 200 pounds for the same size screw.
The major disadvantages of prior art aircraft trim panel fastener mounts are cost and weight. The metal components of such mounts are usually machined, which is an expensive process. Further, the design of prior art aircraft trim panel fastener mounts is such that metal subparts have to be assembled and swaged together--a labor intensive and, thus, expensive process. Prior art aircraft trim panel fastener mounts are undesirably heavy because they are, in part, formed of heavy materials, namely aluminum or steel. The weight of prior fasteners is of major concern in airplane design because each item that adds structural weight to an aircraft causes a corresponding decrease in payload weight.